Empirical mass flow runout analysis: Innovative new tools

May 20, 2021
An idealized representation of a tailings dam breach showing the two runout limit classifications (Ghahramani et al. 2020). Similarly, a three-zone classification system has been developed for rock avalanche impacts.

Negar Ghahramani, Andrew Mitchell, and Scott McDougall

Mass flows of geological materials can travel substantial distances, causing significant loss of life, environmental damage, and economic costs. The Geohazards Research Team within the Geological Engineering program studies a variety of these phenomena, including natural events like rock avalanches and debris flows, and human-related events such as flows resulting from tailings dam breaches. The hazards from these events are largely related to their mobility, how far they travel and how much they spread, which can be quite uncertain. Case studies of real events are key to developing better empirical methods, either based on physical scaling laws, statistical relationships, or a combination of both, to estimate the extent of potential flows. The first stage of both of these pieces of work was to develop consistent definitions and criteria for describing and mapping the case studies. Empirical relationships for both tailings flows and rock avalanches were developed using the new databases which can be used both in academia for future studies and in industry for practical application to risk management problems. This work show the potential for applying similar methods to a wide variety of flow-like processes.